<template>
    <div v-if="editMode == 'edit'" class="v-text" @keydown="handleKeydown" @keyup="handleKeyup">
        <!-- tabindex >= 0 使得双击时聚集该元素 -->
        <div :contenteditable="canEdit" :class="{ canEdit }" @dblclick="setEdit" :tabindex="element.id" @paste="clearStyle"
            @mousedown="handleMousedown" @blur="handleBlur" ref="text" v-html="element.propValue" @input="handleInput"
            :style="{ verticalAlign: element.style.verticalAlign }"
        ></div>
    </div>
    <div v-else class="v-text preview">
        <div v-html="element.propValue" :style="{ verticalAlign: element.style.verticalAlign }"></div>
    </div>
</template>

<script>
import { mapState } from 'vuex'
import { keycodes } from '@/utils/shortcutKey.js'

export default {
    props: {
        propValue: {
            type: String,
            require: true,
        },
        element: {
            type: Object,
        },
    },
    data() {
        return {
            canEdit: false,
            ctrlKey: 17,
            isCtrlDown: false,
        }
    },
    computed: {
        ...mapState([
            'editMode',
        ]),
    },
    methods: {
        handleInput(e) {
            this.$emit('input', this.element, e.target.innerHTML)
        },

        handleKeydown(e) {
            if (e.keyCode == this.ctrlKey) {
                this.isCtrlDown = true
            } else if (this.isCtrlDown && this.canEdit && keycodes.includes(e.keyCode)) {
                e.stopPropagation()
            } else if (e.keyCode == 46) { // deleteKey
                e.stopPropagation()
            }
        },

        handleKeyup(e) {
            if (e.keyCode == this.ctrlKey) {
                this.isCtrlDown = false
            }
        },

        handleMousedown(e) {
            if (this.canEdit) {
                e.stopPropagation()
            }
        },

        clearStyle(e) {
            e.preventDefault()
            const clp = e.clipboardData
            const text = clp.getData('text/plain') || ''
            if (text !== '') {
                document.execCommand('insertText', false, text)
            }

            this.$emit('input', this.element, e.target.innerHTML)
        },

        handleBlur(e) {
            this.element.propValue = e.target.innerHTML || '&nbsp;'
            this.canEdit = false
        },

        setEdit() {
            this.canEdit = true
            // 全选
            this.selectText(this.$refs.text)
        },

        selectText(element) {
            const selection = window.getSelection()
            const range = document.createRange()
            range.selectNodeContents(element)
            selection.removeAllRanges()
            selection.addRange(range)
        },
    },
}
</script>

<style lang="scss" scoped>
.v-text {
    width: 100%;
    height: 100%;
    display: table;

    div {
        display: table-cell;
        width: 100%;
        height: 100%;
        outline: none;
    }

    .canEdit {
        cursor: text;
        height: 100%;
    }
}

.preview {
    user-select: none;
}
</style>